Apple has officially unveiled its Mac App Store, on time as promised, and simultaneously the iPhone 3GS is now available for just $49. All this just as CES kicks off—talk about stealing thunder from every other hardware firm.

When he revealed the Mac App Store last November (only a little while after we first floated the idea), Steve Jobs promised that the new effort would arrive right around now—and here it is. The Apple press release is simple and to the point:

The Mac® App Store℠ is now open for business with more than 1,000 free and paid apps. The Mac App Store brings the revolutionary App Store experience to the Mac, so you can find great new apps, buy them using your iTunes® account, download and install them in just one step. The Mac App Store is available for Snow Leopard® users through Software Update as part of Mac OS® X v10.6.6.

There's also a quote from Jobs: "With more than 1,000 apps, the Mac App Store is off to a great start. We think users are going to love this innovative new way to discover and buy their favorite apps."

The arrival of the App Store is causing much debate online about the changing nature of PC software. Much as the iOS App Store is the key to the iPhone and iPad's success, and beats its competitors app store efforts, the Mac App Store has massive potential to upend the PC software vending market. Early indications suggest Mac Apps will sell for less than the traditional price brackets Mac software's been sold at for decades. This could revolutionize the Mac market, turning it into something that could really allow Macs to challenge the traditional Windows market dominance in enterprise or at home—particularly as it's a one-stop-shop for games, utilities and so on, and even handles updates in a way Windows can't challenge.

Meanwhile, the Wall Street Journal is reporting that AT&T is now selling the iPhone 3GS for just $49—half its previous $99 total. It's a significant move, representing Apple's response to the Android army and AT&T's pre-emptive moves to mitigate against losses from a Verizon iPhone. One could also read it as a sign that the iPhone 5 may be arriving sooner this year than we may have been expecting (leaked parts from the phone also play into this theory).

But what this is really about is stealing CES's thunder. Last year Apple was busily changing the computer game with the iPad, which took over so many blog posts and column inches that practically no other tech news seemed to matter. Apple shuns CES, and even MacWorld, preparing to control its own news flow instead—its release of the iPad news last year, ending decades of rumors, was timed to squash other news coming from the show. This year, the iPad 2 is still under wraps, and there's no official word on the much anticipated iPhone for Verizon. So instead Apple is using other means to influence the flow of news from CES.

There are reports that Apple's restricting its employees from taking time off this month, ahead of a raft on announcements due at the end of the month or in February. So whatever it has coming for us in early 2011 we will know soon.

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